Water intrusion into buildings is a massive and growing problem. Leaking buildings cost homeowners, commercial property owners and property insurers hundreds of millions of dollars every year. Even the smallest leaks that channel water into building walls can cause expensive problems. Structural damage to plywood sheathing and stud walls due to wood rot has been commonplace for decades. Black mold or toxic mold that grows in the wet walls is known to cause severe physical problems for occupants as well as severe fiscal problems for builders and insurance companies.
Early detection and location of building envelope penetration will allow the builder or owner to identify developing problems and carry out minor repairs. These homeowners, builders, and insurance companies can avoid high costs resulting from extensive structural damage, health problems, insurance claims and potential lawsuits
There are several types of moisture detection sensors available for detecting water leaks.
In U.S. Pat. No. 6,175,310 (Gott) issued Jan. 16, 2001 there is disclosed an arrangement which uses exposed conductors on a tape of a hygroscopic material where the current across the conductors is detected to detect moisture enveloping the tape.
In U.S. Pat. No. 6,377,181 (Kroll) issued Apr. 23, 2002 there is disclosed an arrangement which uses probes which are each connected to a conductor pair communicating with a central monitor which issues an alarm when moisture above a threshold is detected.
In U.S. Pat. No. 6,144,209 (Raymond) issued Nov. 7, 2000 there is provided an arrangement which describes a location method using a combination of specially designed insulated and detection conductors cabled together in a form helix. This design while useful for detection and location of water on floor like surfaces can not be placed between the roof deck and waterproof membrane because of the large overall dimensions and the susceptibility of the cable design to crushing and shorting.
U.S. Pat. No. 4,502,044 (Farris) issued Feb. 26th 1985 discloses a plurality of sensor elements defined by side by side pairs of conductors which are adapted to be mounted in two walls of a building and which connect to a central control unit. The control unit uses a transistor which acts to detect when voltage across a resistor reaches a value sufficient to turn on the transistor to emit an alarm signal.
British Patent Application 2,235,535 (Stewart) published 1991 discloses a plurality of sensor elements defined by tapes 3 which are mounted in walls of a building and connect to a central control unit in the form of a leak detection
U.S. Pat. No. 5,081,422 (Shih) issued Jan. 14th 1992 discloses in general a plurality of moisture sensor elements each defined by a side by side pairs of conductors which have a resistance characteristic which varies in relation to a moisture content. Shih also discloses the use of probes which are connected to the wires and are driven into the material on which the wires are attached.
The present Applicants also disclose arrangements in Published PCT Application WO/05/10837 published Feb. 3, 2005. These arrangements use detection tapes and probes are suited for detecting water intrusion in selected areas of a building structure. Also in U.S. application Ser. No. 11/229,312 filed Sep. 19, 2005 entitled “A MOISTURE DETECTION SENSOR TAPE WITH LEAK LOCATE”, which corresponds to Canadian application Serial No: 2,520,202 filed Sep. 19, 2005, is disclosed an improved tape using four conductors which allow a location process to be used to locate the position of the leak along the tape. The disclosures of the above application of the present Applicant are incorporated herein by reference or may be reviewed for further details not disclosed herein.